When Mary Jo Tozier of Bucksport semi-retired a few years ago from her family’s grocery store business, the active then-60-year-old was surprised to find herself with too much time on her hands.

“It turns out you don’t really want that much time to yourself when you retire,” she said. “Right after I retired, I thought, ‘OK, now I’ve got to do something. I can’t just sit around and organize my house all day.’”

In the local paper, she found a short notice about an exercise program for seniors. She felt too young and healthy to join as a participant, but the story also indicated the program was looking for volunteers to lead the classes. Intrigued, she signed up for training, which included enrolling in a class. Within a few months, she was asked to co-lead the group.

So now, a little before 9 a.m. every Wednesday and Friday, Tozier arrives at The Heritage, a property of the Brewer Housing Authority, and starts setting up for the Bone Builders workout class that meets in the big community room there.

On a recent Wednesday, she was joined by co-leader Linda Hedman, who helped arrange straight-back chairs in a big circle and set out hand and ankle weights. Pretty soon, the class members start filtering in — about a dozen men and women in their 60s, 70s, 80s and 90s, laughing, cracking jokes and catching up on news as they settled in and got ready for a surprisingly challenging workout.

A leisurely warm-up loosened stiff necks and shoulders, stretched arms in slow, swim-like strokes and limbered up rigid backbones and rib cages. The warm-up was followed by a series of slow, controlled, rhythmic exercises — squats, leg-lifts, abdominal crunches and more — modified for safety and using graduated weights to increase the challenge and the benefit. Tozier and Hedman took turns leading the exercises, but participants were clearly familiar with them all and counted out the repetitions and holds in cheerful unison. There were short breaks for rest and water, but everyone seemed to appreciate the good workout.

Former fighter pilot Ed Hendrickson, 96, of Brewer said he has been relying on Bone Builders for the past 11 years to help keep him in shape for downhill skiing. He hasn’t skied yet this winter, but hopes conditions will improve so he can.

“If I weren’t doing this, I probably wouldn’t be able to go,” he said, strapping on an ankle weight for the “slow Rockettes” leg lifts.

Across the circle, 70-year-old retired librarian Judy Leighton of Orrington, who suffers from osteoarthritis, said the program has improved her balance, mobility and strength.

“I retired 2½ years ago and was doing a whole lot of nothing,” she said. After a friend brought her to Bone Builders, she said, “I was amazed to see how weak I was.”

Since she started coming regularly, she has seen a lot of improvement, even after breaking her leg in a fall last year.

Bone Builders classes are free and open to anyone 50 and older, with permission from a physician. Leaders, who are all volunteers, must be 55 or older. The program is offered by RSVP, or the Retired and Senior Volunteer Program, a federal program housed at the Maine Center on Aging at the University of Maine in Orono. RSVP volunteers here serve a four-county area, leading Bone Builders classes, working on reading skills with preschoolers, building science and math skills with elementary students, and, in partnership with veterans organizations, supporting military veterans and their families.

But Bone Builders has been around the longest of these programs and has the greatest reach, according to RSVP director Paula Burnett at the Maine Center on Aging. There are about 26 volunteer Bone Builder leaders staffing 10 sites in Penobscot, Piscataquis, Hancock and Washington counties, reaching a total enrollment of about 150 participants.

“The goal is to increase muscle strength, build bone density, become more flexible and prevent falls,” Burnett said. In the process, leaders and class members alike enjoy regular socialization, affiliation with a group of peers and a greater sense of overall well-being.

“It works both ways,” Burnett said. “The [volunteer] leaders get as much out of it as the participants.”

Across the river in Bangor, Donna Dwyer of Hampden co-leads a Bone Builders class at the Sunbury Village senior living and retirement community. Retired since 2011 from her work as an elementary physical education teacher, Dwyer said she soon grew restless.

“I needed something to do,” she said. A longtime fitness buff, Dwyer decided to add Bone Builders to her weekly schedule of workouts and other physical activity, which includes gym time and tai chi as well as outdoor sports such as hiking and cross-country skiing. “It’s important to stay as active as possible as we age,” she said.

While Sunbury Village donates space for the workouts, most of the people in her class don’t live there.

“The oldest in the class is almost 90 and the youngest is myself, at 65,” she said.

She trusts the program’s efficacy on a common-sense basis as well as from personal observation.

“One woman had to take time off for knee replacement surgery, but she was back with us in less than a month,” she said. “But really, it’s all their comments. They all say they just feel better, and that’s evidence for me.”

Bone Builders surveys all participants every six months, asking how long they’ve been in the program, how much weight they’re using in their workouts and whether the program has increased their ability to be physically active in their day-to-day lives. Burnett at the Center on Aging said participants consistently report progress, including better balance, strength and endurance.

“One woman told us she hadn’t been able to reach up on a high shelf and get her gravy boat for years, but after being in the program, she could,” Burnett said.

While that kind of anecdotal evidence lends support to the program’s popularity, a push is underway at the Maine Center on Aging to determine if participation in Bone Builders is associated with lower health care spending, fewer bone fractures and other, more measurable goals.

For more information about leading or joining a Bone Builders class, call Paula Burnett at 262-7926 or email Paula.Burnett@maine.edu.

Meg Haskell

Meg Haskell is a curious second-career journalist with two grown sons, a background in health care and a penchant for new experiences. She lives in Stockton Springs. Email her at mhaskell@bangordailynews.com.